If you cannot simply double click on a folder (the 'Extensions' folder, for example) to open it, then you already have problem(s) with the currently running System (version 9.1). It is best to resolve any System problem(s) - before updating / upgrading the System.
Since you have only recently installed System 9.0.x and then 9.1, consider this:
Reinstall System 9.0.x, making sure to have the hard drive completely erased prior to its installation.
Once System 9.0.x is installed - test it. Try opening folders, launching applications, viewing files, etc. if successful, then install the 'System 9.1 Update'.
Test System 9.1. If successful, then install the 'System 9.2.1 Update' (see 'Once System 9.1 is installed and properly operating:' below).
Test System 9.2.1. If successful, then install the 'System 9.2.2 Update' (see below for the 'Mac_OS_9.2.2_Update' link).
Finally, test System 9.2.2.
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Once System 9.1 is installed and properly operating:
Boot the Mac as normal, via its internal hard disk drive. Insert the System 9.2.1 CD, double click on the 'Mac OS 9.2.1' (if an actual bootable CD) or 'Mac OS 9.2.1 Update' application (if just the update only CD).
Or, you could go to '
Mac OS 9.2.1: Document and Software' and download 'Mac_OS_9.2.1_Update.smi.bin'. Then, at '
Mac OS 9.2.2: Document and Software', download 'Mac_OS_9.2.2_Update.smi.bin'.
Both of which are not bootable; but, installable when the Mac is booted with System 9.1.x, and then System 9.2.1 - respectively.
